Risk factors for bloodstream infections caused by extended-spectrum β-lactamase-producing Escherichia coli and Klebsiella pneumoniae

• Published in: The Brazilian journal of infectious diseases Vol. 15; no. 4; pp. 370 - 376
• Main Authors: Ferrández Quirante, Olivia, Grau Cerrato, Santiago, Luque Pardos, Sonia
• Format: Journal Article
• Language: English
• Published: Elsevier Editora Ltda 01.07.2011
• Subjects: bacteremia; risk factors; β-lactamases; β-lactamases; risk factors; bacteremia
• ISSN: 1413-8670
• DOI: 10.1016/S1413-8670(11)70207-0

The objective of this study was to identify risk factors for bacteremia by extended-spectrum β-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae. Retrospective case-control study performed in a 450-bed acute care academic tertiary hospital in Barcelona, Spain. Cases included 53 patients with ESBL-producing E. coli or K. pneumoniae bacteremia, and 159 controls with non-ESBL-producing E. coli or K. pneumoniae bacteremia. Controls were matched in a 3:1 ratio to case patients according to species of infecting organism, age, and severity of illness in the 24-48h before blood sample collection for culture calculated by the Simplified Acute Physiology Score (SAPS II) system. Previous antimicrobials were more frequently administered to cases than to controls (56.5% vs 17%, p<0.001). Binary logistic regression showed that the number (>2) of different families of antimicrobials received within 90 days before bloodstream infection was the only predictor of ESBL-producing E. coli or K. pneumoniae in blood culture (OR=2.29, 95% CI 1.35−3.88, p=0.002). Previous use of different families of antimicrobials (more than two) in patients with bloodstream infection caused by E. coli or K. pneumoniae increased the risk for ESBL-producing strains.